Removal of residual particulate matter from filter media

ABSTRACT

A method for removing residual filter cakes that remain adhered to a filter after typical particulate removal methodologies have been employed, such as pulse-jet filter element cleaning, for all cleanable filters used for air pollution control, dust control, or powder control.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was made with U.S. Government support under the U.S.Department of Energy Cooperative Agreement No. DE-FC26-98FT40320. Thegovernment has certain rights in this invention.

BACKGROUND

Filters made from various filtration media and shapes are employed as aparticulate pollution control approach for many processes. Typically,many filters are packaged into a housing that may include a few filtersto over 10,000 filters. As the filters collect dust from the process,pressure drop builds up across the filter to the point where the filtersneed to be cleaned. Common cylindrically-shaped bag filters aretypically cleaned by a pulse of high-pressure air injected into the topof the filter, which will dislodge much of the dust collected on theoutside of the filter elements and allow the dust to fall to acollection hopper. Filters may also be cleaned by mechanical shaking orwith a low-pressure, reverse-air mechanism. The filters are typicallycleaned as often as every few minutes to as long as several hours. Withmultiple cleanings, the filters develop high pressure drop over timebecause of a thin but tenacious amount of residual dust that does notclean off by normal filter cleaning methods. If the pressure drop is toohigh and the residual dust will not clean off, the filters are said tobe blinded. In many cases, the filters have to be replaced, not becausethey are worn, but because of the high pressure drop due to filterblinding.

To minimize the size of a filter housing containing filters, it isdesirable for it to operate at a high filtration velocity, calledair-to-cloth ratio (A/C ratio). One of the biggest obstacles tooperation of large-scale filter housings at high A/C ratios is removingthe residual dust from the filters. The general term for the flowresistance due to the dust left on the filters after normal cleaning is“residual drag,” which is simply the pressure drop across the filterdivided by the filtration velocity. For a fabric type filter operatingat an A/C ratio of 12 ft/min that has an after-cleaning pressure drop ofabout 6-in. W.C., the residual drag would be 0.5-in. W.C./ft/min. Thiscompares with a new fabric type filter having a residual drag of onlyabout 0.1-in. W.C./ft/min for a typical membrane fabric. Many timesfilter residual drag may reach a value over 1.0-in. W.C./ft/min, whichmeans significant power is required by a fan maintaining gas flowovercoming the high residual drag of a filter. Further, the filteringprocess may also be limited by the fan's capacity to draw gas flowthrough the filter. The major incentive to operate these filters at ashigh of an A/C ratio as possible is economic advantage.

SUMMARY

The present subject matter relates to a method for removing residualparticulate matter that remains adhered to a filter even after typicalfilter cleaning methodologies have been employed, such as pulse jetfilter cleaning. It applies to all cleanable filters used for airpollution control, dust control, or powder product capture.

A method for removing residual particulate matter from a filter in aparticulate matter control device comprising applying an adhesivesubstance to the surface of the filter where the substance adheres tothe residual particulate matter on the filter; and removing the residualparticulate matter from the filter by removing the adhesive substancefrom the filter together with at least a portion of the residualparticulate matter.

Additionally, a method for reducing residual filter drag of a filter bylowering such filter residual drag of a filter thereby enabling greatersystem efficiencies by decreasing the power required to operate blowers.The method of reducing residual particulate matter from a filter alsogreatly increases the lifespan of a set of filter bag type filters,reducing labor and material costs. Finally, it offers a method by whichmore aggressive filter designs may be utilized where pressure drop andfilter blinding were once limiting factors.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which are not necessarily drawn to scale, like numeralsmay describe similar components in different views. Like numerals havingdifferent letter suffixes may represent different instances of similarcomponents. The drawings illustrate generally, by way of example, butnot by way of limitation, various embodiments discussed in the presentdocument.

FIG. 1 is a schematic of a typical pulse-jet filter arrangement.

FIG. 2 is a schematic of particulate matter (PM) carried within a dirtygas stream 1 and collected on the surface of a filter 2, termed “filtercake 3”.

FIG. 3 is a plot depicting typical filter blinding phenomena encounteredin many filter applications.

FIG. 4 includes a series of samples associated with the present subjectmatter.

FIG. 5 is a schematic of the adhesive substance sprayed directly anduniformly onto all filter elements via an array of nozzles 22 dispersedthroughout the filter housing.

FIG. 6 is a schematic of the adhesive substance 23 sprayed indirectlyand uniformly onto all filters via nozzles mounted in either the primarygas inlet 24 or a secondary gas inlet 25.

FIG. 7A, FIG. 7B, and FIG. 7C include photographs showing results of thecoating and drying process after deposition of the adhesive substanceonto blinded filters.

FIG. 8 is a photograph detailing the results of the coating and dryingprocess after deposition of the adhesive substance onto alternate filtersurfaces 32.

DETAILED DESCRIPTION

The term “particulate matter (PM)” as used herein refers to a substancethat consists of separate particles, especially airborne pollution, thatcan be controlled by collection on a filter. The particulate matter,once collected on a filter typically has the consistency of a bulkpowder.

The term “filter” as used herein refers to a device made of orcontaining a porous material used to collect particles from a liquid orgas passing through it.

The term “filter cake” as used herein refers to the particulate matterthat accumulates on a filter used to collect particles from a gas orliquid stream.

The term “residual particulate matter” as used herein refers to theparticulate matter that remains on a filter after the filter has beencleaned by ordinary process methods.

The term “filter blinding” as used herein refers to the condition wherea filter becomes plugged with residual particulate matter so thatadequate gas flow through the filter is no longer possible.

The terms “pressure drop” and “differential pressure”, as used hereinrefer to the difference in static pressure between the upstream anddownstream sides of a filter because of the energy loss that occurs fromforcing gas flow through the filter.

The term “in. W.C.” as used herein refers to inches of water column, acommon unit of pressure or pressure drop in industrial processes.

The term “adhesive substance” as used herein refers to a material thathas the properties such that it will adhere to other materials that itcontacts.

The term “A/C Ratio” as used herein refers to air to cloth ratio, alsocalled face velocity, is the volume flow rate of a gas through a filterdivided by the cross sectional area of the filter.

The term “pulse-jet” as used herein refers to a method used inindustrial filters to remove a filter cake from the filter where a shortpulse or jet of high-pressure air is directed to the inside of acylindrical filter element which momentarily reverses the direction ofgas flow through the filter and dislodges the filter cake from theoutside of the filter.

The term “gelatine” as used herein refers to a highly processedsubstance made from the hides and bones of bovine, equine, and porcineanimals.

The term “starch” as used herein refers to a fine, powdery flour fromthe endosperm of a grain food or from the root of a plant or similarsynthetic materials.

The term “fluoroelastomer” as used herein refers to any of a class offluorinated long-chain polymers with an intrinsic quality of highstretchability.

In embodiments, the present subject matter reduces the residual filterdrag caused by excessive residual particulate matter buildup. Becausethis residual buildup is not removable by normal operational methods,the present subject matter also greatly reduces filter blinding overtime. One advantage of the present subject matter is to increase thecost-effectiveness of filter baghouses and other filtration systems byreducing filter element replacement costs over time. Another advantageis to decrease system power consumption during normal bag operation bydecreasing mean airflow resistance during the lifetime of a filterelement. Another advantage is to permit expansion of the operationalenvelope of the filter system, resulting in a more aggressive design topermit higher airflow, a smaller footprint, and lower overall capitalcosts.

In some embodiments, the subject matter is a method for removal ofresidual filter cake, including injecting an adhesive substance into thefilter housing, collecting the adhesive on the surface of the targetedfilter elements, drying or curing the adhesive coating, and removing theadhesive coating along with the residual PM.

In one example, the adhesive substance is comprised of anenvironmentally friendly substance, causing no undue effects to theenvironment after disposal. In some embodiments, adhesive substances mayinclude a food-type gelatine solution, various starch solutions(produced from any of a family of specific food starches), a dilutefluoroelastomer solution, or a combination thereof. Curedfluoroelastomers can typically be stretched up to 400% with nohysteresis. Fluoroelastomers also possess a superior resistance tochemical attack. The fluoroelastomer class may provide a benefit in thata cured fluoroelastomer will stretch, but not adhere tightly to manysurfaces, thus enabling easy release from the filter surface.

In embodiments, a variety of adhesive substances may be used within thisdescription because a number of different materials produce similarresults in terms of residual PM removal. Such adhesive substances willall attach to and partially permeate a residual filter cake, dry andset, and be easily removed from the filter by one of the methodsdescribed herein.

Referring now to FIG. 1, there is shown a schematic of a typicalpulse-jet filter arrangement. In a typical filter system, particulatematter 5 borne within the flow of gas 6 into the filter housing 7collects in the form of filter cake 8 on the surface of cylindricalfilters 9. The particulate matter is thus disengaged from the gasstream, and a PM-free gas stream 10 exits the filter housing. Either ona timed cycle or on a cycle triggered by pressure drop across thefilters, a pulse of air 11 is directed into the internal volume 12 ofthe individual filters, causing momentary and powerful reversal of gasflow. Filter cake 13 is dislodged from the filter surface and falls intothe filter hopper 14 and is eventually removed via screw conveyor 15 orpneumatic discharge.

Filter blinding may occur rapidly, within a short time of a week orless, or more slowly, within a time of several months to a year or more.In either case, the filter blinding limits the gas flow through thefilter so that normal operation is no longer possible due to highpressure drop across the filter. To restore normal operation wouldrequire expensive replacement of the filter, even though the filter isnot otherwise deteriorated. Described is a method to reverse the effectsof filter blinding, greatly extending the life of the filter.

Referring now to FIG. 2, there is shown a schematic of how PMaccumulates on the filter to create a filter cake. Specifically, FIG. 2is a schematic of particulate matter (PM) carried within a dirty gasstream 1 and collected on the surface of a filter 2, termed “filter cake3”. Fluid flow (typically gaseous) carries PM to the surface of thefilter, which acts as a barrier to solid matter, but allows gas to flowfreely through it. The PM is deposited and builds thickness. A gasstream 4 free of PM exits the filter housing.

Referring now to FIG. 3, there is shown a plot depicting typical filterblinding phenomena encountered in many filter applications. Over arelatively short span of time, filter cake grows thicker, causing asteady rise in pressure drop across the filter as shown by the rampingrise in pressure. A cleaning mechanism occasionally dislodges filtercake, thus sharply decreasing the pressure drop across the filter, asshown by the near-vertical drop in pressure coincident with the pulses.However, typically, the pressure drop caused by dislodging the filtercake is less than the pressure drop caused by the accumulation of thefilter cake, and thus, over a longer span of time and successivecleaning efforts, the residual pressure drop present after the cleaningprocess increases with each pulse. This is due to incomplete removal ofthe filter cake during each successive cleaning process. This is knownas “filter blinding” and is depicted by the generally rising trend inboth the peak pressures and minimum pressures for the cycles shown.

FIG. 4 includes a sequence of elements associated with an example of thepresent subject matter. The left-most illustration represents a cleanfabric filter at a time prior to exposure to particulate matter. Thenext illustration represents cake build-up 19 (also referred to as ablinded filter 19). The next illustration in the sequence illustratesspray on 20 and, as shown, this is distributed on the cake build-up. Theadhesive substance dries and begins to crack 20. The next illustrationdepicts dry and crack 21 (autoinitiation of peeling and sloughingbegins). The right-most illustration depicts flake or molt off and ismarked ‘peel’ in which the peeling adhesive substance and attachedparticulate matter from the residual filter cake is sloughed off thefilter 21 either naturally with help from gravity or by use of aconventional filter cleaning mechanism such as, but not limited to,pulse-jet cleaning or reverse gas cleaning.

With any of the adhesives described herein, the method of introductionmay be the same. In some embodiments, the adhesive substance may beinjected into the filter housing via the inlet process gas stream, viaan auxiliary inlet, or via direct application to the filter elementswith a spray mechanism or by dripping or pouring of the adhesivesubstance. In embodiments where the introduction occurs via inletprocess gas stream or auxiliary inlet, the adhesive should be atomizedto a mean particle size capable of being carried by the process gasstream to the filter surface. At a small enough mean particle diameter,the aerodynamic effects of the process gas stream overpower the effectsof gravity, causing the particles to be entrained in the flow ratherthan pulled down by gravity. In other embodiments where directapplication occurs, inertial effects of the mean velocity vector of theatomized material spray overpower the effects of gravity in a similarmanner. It should be appreciated by those skilled in the art that otheralternative injection techniques are also possible.

Referring now to FIG. 5, there is shown a schematic of the adhesivesubstance sprayed directly and uniformly onto all filter elements via anarray of nozzles 22 dispersed throughout the filter housing.

Referring now to FIG. 6, there is shown a schematic of the adhesivesubstance 23 sprayed indirectly and uniformly onto all filter elementsvia nozzles mounted in either the primary gas inlet 24 or a secondarygas inlet 25. The adhesive substance is entrained in the inflow 26, 27of gas and carried to the surface of the filters 28.

In one example of an injection method, the adhesive substance is drawnto the filter surface, collecting there to a predetermined thickness.This adhesive substance coating partially permeates the residual filtercake as it dries or cures in place. Because it partially permeates theresidual filter cake, the adhesive substance entraps a large portion ofthe particulate matter comprising the residual filter cake within thematrix of the drying coating. When the coating is dry, it can then pullthe residual filter cake away from the surface of the filter via variousmethods known to those skilled in the art, such as a pulse of gasinjected into the filter element(s). Collection of the adhesivesubstance, drying of the material, and removal of the adhesive substancecoating can all occur with or without process gas or airflow through thefilter. Additionally, removal of the adhesive substance coating mayoccur with or without heat, utilizing natural air flow.

As an example, it was observed that the filter cakes tested allexhibited a somewhat hydrophilic nature. Many of the water-based,low-surface-tension solutions tested, such as gelatine solutions,cornstarch solutions, and a commercial water-based liquid mask product,were drawn into the filter cake by capillary action. Because the filtercake had been absorbed into the matrix of the drying coating, itremained embedded in the matrix of the coating upon completion of thedrying process. As the coating dried, it began to crack and peel becauseof the chemistry of the drying of hydrated starch. The filter cakeparticles were then peeled away from the filter surface along with thedried starch matrix. As an integral part of the process, the peelingphenomenon occurred without filter pulsing or other external force.

Starch chemistry holds the explanation of this phenomenon ofautoinitiation of cracking and peeling of the drying coating. Cornstarchcomprises two different base monomers: approximately 25% amylose and 75%amylopectin. Amylose is a linear chain of glucose molecules. Amylopectinis a branched chain of glucose molecules. Amylose is water-soluble andwill form a gel because of hydrogen bonding between the linear chains.Amylopectin is not soluble in water but will cause a suspension tothicken because of its branched structure.

When a slurry of cornstarch in water is heated, the cornstarch granulesabsorb water and swell. Near the slurry's gelatinization temperature,the granules absorb even more water and lose their crystallinestructure. This structural change is irreversible. Starch moleculesbegin to leach out of the swollen granule, and the mixture becomes aviscous solution.

Upon drying on the filter, autoinitiation of cracks in the dryingcoating becomes apparent. Also, a curling effect beginning at thesecracks is evident. This can be explained by a number of mechanisms.First, acids hydrolyze (“cut with water”) glucosidic bonds in the starchsolution. These cuts are the sites of many of the autoinitiated cracksin the drying cornstarch coating. Agitation due to syneresis (loss ofwater) in the drying solution, is also responsible for the destructionof some of the swollen granules, causing further breaks in the coating.

The curling effect can be explained by mass-transfer effects within theadhesive substance coating. The outside depths of the coating farthestfrom the hydrophobic membrane of the filter dry first. The evaporationof water causes the granules to shrink. The granules farther upstream inthe airflow will shrink faster. This dehydration gradient within thecoating depth causes the coating to curl in the direction of the driestlayers in the coating.

Referring now to FIG. 7, there is shown a series of photographsdetailing the expected results of the coating and drying process afterdeposition of the adhesive substance onto blinded filters. FIG. 7A ofthe photograph shows the appearance of an aqueous starch solutionembodiment of the present subject matter just after deposition of theadhesive solution onto the blinded filter bag. Note the wet appearance29 and uniform coating thickness. FIG. 7B shows the effects of drying ofthe applied adhesive substance, and subsequent autoinitiation of peelingand soughing of the adhesive/PM mixture away from and off of the cleanfilter surface. FIG. 7C shows the nearly completely restored surface 30of the filter with all residual cake removed 31 in many areas.Successive pulses will completely remove the remains of the adhesivesubstance and residual filter cake bonded to the adhesive substance.

Referring now to FIG. 8, there is shown a photograph detailing theexpected results of the coating and drying process after deposition ofthe adhesive substance onto alternate filter surfaces 32. In thisembodiment, the filter surface 32 is metallic instead of more commonfabric filter media. A peeling and sloughing action similar to thatobserved in FIG. 7 is observed here 33.

EXAMPLES

As a specific example, a cornstarch solution (146 grams of cornstarchper liter of water) at 140° F. was directly applied to the filter cake.As the solution dried, it encased much of the persistent residual filtercake within the matrix. A property of this cornstarch solution is thatit cracks apart as it dries, peeling away from the fabric filter surfaceas it dries. This greatly enhances the efficacy of the procedure,requiring less forceful removal mechanisms. The remaining, clingingflakes of filter cake-laced coating can be easily removed with amechanism such as a pulse-jet of gas typically used in pulse-jet cleanedfilter systems.

In addition to cornstarch solution of 146 grams of cornstarch per literof water, other solutions or concentrations are also contemplated. Forinstance, other examples include a coating material including cornstarchat a ratio of cornstarch 122 grams per liter, 104 gm/L, or other ratio.In one example, the coating material includes gelatin at a ratio of 14gm/L.

Referring again to FIG. 7A shows a filter laden with a residual filtercake immediately after being sprayed with a cornstarch solution. FIG. 7Bshows the cornstarch coating after the coating has completely dried.Note that no pulse has yet been imparted to the bag. All peeling evidentin this frame is solely a function of the chemistry of the starchdehydration. Finally, FIG. 7C shows a close-up of the bag surface afterfilter element pulsing has taken place. Note the like-new condition ofthe filter fabric.

In summary, as described herein there are many benefits to using themethod described herein, including restoring the permeability of a usedfilter, reversing the blinding of a filter, increasing the lifespan offilter media, increasing the average face velocity of a filter, reducingthe pressure drop across a filter, reducing the energy required to movegas through the filter, and reducing the energy required to clean thefilter media.

Additional Notes

The above detailed description includes references to the accompanyingdrawings, which form a part of the detailed description. The drawingsshow, by way of illustration, specific embodiments in which theinvention can be practiced. These embodiments are also referred toherein as “examples.” Such examples can include elements in addition tothose shown or described. However, the present inventors alsocontemplate examples in which only those elements shown or described areprovided. Moreover, the present inventors also contemplate examplesusing any combination or permutation of those elements shown ordescribed (or one or more aspects thereof), either with respect to aparticular example (or one or more aspects thereof), or with respect toother examples (or one or more aspects thereof) shown or describedherein.

All publications, patents, and patent documents referred to in thisdocument are incorporated by reference herein in their entirety, asthough individually incorporated by reference. In the event ofinconsistent usages between this document and those documents soincorporated by reference, the usage in the incorporated reference(s)should be considered supplementary to that of this document; forirreconcilable inconsistencies, the usage in this document controls.

In this document, the terms “a” or “an” are used, as is common in patentdocuments, to include one or more than one, independent of any otherinstances or usages of “at least one” or “one or more.” In thisdocument, the term “or” is used to refer to a nonexclusive or, such that“A or B” includes “A but not B,” “B but not A,” and “A and B,” unlessotherwise indicated. In this document, the terms “including” and “inwhich” are used as the plain-English equivalents of the respective terms“comprising” and “wherein.” Also, in the following claims, the terms“including” and “comprising” are open-ended, that is, a system, device,article, or process that includes elements in addition to those listedafter such a term in a claim are still deemed to fall within the scopeof that claim. Moreover, in the following claims, the terms “first,”“second,” and “third,” etc. are used merely as labels, and are notintended to impose numerical requirements on their objects.

Method examples described herein can be machine or computer-implementedat least in part. For example, a computer operated system can beconfigured to deliver a coating material in response to a timing signalor in response to a measured parameter (such as a differentialpressure). A computer can be configured to control delivery of thecoating material and control the operation of other systems configuredto remove the particulate.

Some examples can include a computer-readable medium or machine-readablemedium encoded with instructions operable to configure an electronicdevice to perform methods as described in the above examples. Animplementation of such methods can include code, such as microcode,assembly language code, a higher-level language code, or the like. Suchcode can include computer readable instructions for performing variousmethods. The code may form portions of computer program products.Further, in an example, the code can be tangibly stored on one or morevolatile, non-transitory, or non-volatile tangible computer-readablemedia, such as during execution or at other times. Examples of thesetangible computer-readable media can include, but are not limited to,hard disks, removable magnetic disks, removable optical disks (e.g.,compact disks and digital video disks), magnetic cassettes, memory cardsor sticks, random access memories (RAMs), read only memories (ROMs), andthe like.

The above description is intended to be illustrative, and notrestrictive. For example, the above-described examples (or one or moreaspects thereof) may be used in combination with each other. Otherembodiments can be used, such as by one of ordinary skill in the artupon reviewing the above description. The Abstract is provided to complywith 37 C.F.R. §1.72(b), to allow the reader to quickly ascertain thenature of the technical disclosure. It is submitted with theunderstanding that it will not be used to interpret or limit the scopeor meaning of the claims. Also, in the above Detailed Description,various features may be grouped together to streamline the disclosure.This should not be interpreted as intending that an unclaimed disclosedfeature is essential to any claim. Rather, inventive subject matter maylie in less than all features of a particular disclosed embodiment.Thus, the following claims are hereby incorporated into the DetailedDescription, with each claim standing on its own as a separateembodiment, and it is contemplated that such embodiments can be combinedwith each other in various combinations or permutations. The scope ofthe invention should be determined with reference to the appendedclaims, along with the full scope of equivalents to which such claimsare entitled.

What is claimed is:
 1. A method for removing residual particulate matterfrom a filter in a particulate matter control device, the methodcomprising: applying an adhesive substance to a surface of the filterfor the adhesive substance to adhere to at least a portion of theresidual particulate matter on the surface of the filter; and removingthe residual particulate matter from the filter by removing the adhesivesubstance from the filter together with at least a portion of theresidual particulate matter.
 2. The method of claim 1, wherein at leasta portion of the adhesive substance permeates a portion of a filter cakeformed by the residual particulate matter on the filter.
 3. The methodof claim 1, wherein applying an adhesive substance includes forming acoating of the adhesive substance to adhere to a portion of the residualparticulate matter on the filter.
 4. The method of claim 3, wherein theremoval process includes flaking off of the coating from a portion ofthe surface of the filter.
 5. The method of claim 1, wherein theremoving at least a portion of the residual particulate matter includesthe use of a dehydration gradient and associated contracting chemicalbonds of the coating to cause the adhesive substance to peel from thesurface of the filter for attached or embedded residual particulatematter to peel away from the filter surface.
 6. The method of claim 1,wherein applying the adhesive substance onto a surface of the filterincludes spraying the adhesive substance into the particulate mattercontrol device having a filter.
 7. The method of claim 6, whereinapplying the adhesive substance includes injecting a spray of theadhesive substance into a gas duct upstream of the particulate mattercontrol device having a filter for transporting the spray onto thesurface of the filter.
 8. The method of claim 7, wherein the spray isinjected into the gas duct upstream of the particulate matter controldevice having a filter during operation of the particulate mattercontrol device.
 9. The method of claim 7, wherein the spray is injectedinto the gas duct upstream of the particulate matter control devicehaving a filter during ambient conditions.
 10. The method of claim 6,wherein applying the adhesive substance includes using nozzles in asecondary gas inlet to cause the spray to be carried onto the surface ofthe filter.
 11. The method of claim 1, wherein applying the adhesivesubstance includes applying the adhesive substance directly onto thesurface of the filter.
 12. The method of claim 1, wherein applying theadhesive substance includes applying the adhesive substancesubstantially uniformly to a portion of the surface of the filter. 13.The method of claim 1, wherein applying the adhesive substance includesapplying the adhesive substance by dripping or pouring the adhesivesubstance onto a portion of the surface of the filter.
 14. The method ofclaim 1, wherein the adhesive substance includes one of a solution orsuspension of starches, gelatines, and other polymers.
 15. The method ofclaim 1, wherein removing the residual particulate matter includesremoving the residual particulate matter from a portion of the surfaceof the filter by pulse cleaning of the filter.
 16. The method of claim1, wherein removing the residual particulate matter includes removingthe residual particulate matter from the portion of the surface of thefilter by brushing the portion of the surface of the filter, shaking thefilter, using an air-jet on the portion of the surface of the filter,and using acoustical energy directed to the portion of the surface ofthe filter.
 17. The method of claim 1, further comprising drying aportion of the surface of the filter using one of heated air, unheatedair, or drying using substantially no heat and no air.
 18. A method forremoving at least some particulate matter and residual particulatematter from a filter in a particulate matter control device, the methodcomprising: removing at least a portion of the particulate matter from afilter in a particulate matter control device; applying an adhesivesubstance to the surface of the filter where the adhesive substanceadheres to the residual particulate matter on the filter; and removingthe residual particulate matter from the filter by removing the adhesivesubstance from the filter together with at least a portion of theresidual particulate matter.
 19. The method of claim 18, wherein atleast a portion of the adhesive substance permeates a portion of afilter cake formed by the residual particulate matter on the filter. 20.The method of claim 18, wherein applying an adhesive substance includesforming a coating of the adhesive substance to adhere to a portion ofthe residual particulate matter on the filter.
 21. The method of claim18, wherein the removing at least a portion of the residual particulatematter includes the use of a dehydration gradient and associatedcontracting chemical bonds of the coating to cause the adhesivesubstance to peel from the surface of the filter for attached orembedded residual particulate matter to peel away from the filtersurface.
 22. The method of claim 18, wherein applying the adhesivesubstance onto a surface of the filter includes spraying the adhesivesubstance into the particulate matter control device having a filter.23. The method of claim 22, wherein applying the adhesive substanceincludes injecting a spray of the adhesive substance into a gas ductupstream of the particulate matter control device having a filter fortransporting the spray onto a the surface of the filter.
 24. The methodof claim 23, wherein the spray is injected into the gas duct upstream ofthe particulate matter control device having a filter during operationof the particulate matter control device.
 25. The method of claim 24,wherein the spray is injected into the gas duct upstream of theparticulate matter control device having a filter during ambientconditions.
 26. The method of claim 25, wherein applying the adhesivesubstance includes using nozzles in a secondary gas inlet to cause thespray to be carried onto the surface of the filter.
 27. A method forreducing residual filter drag for a filter having particulate matter onat least a portion thereof, the method comprising: applying an adhesivesubstance to the surface of the filter where the adhesive substanceadheres to the residual particulate matter on the filter; and removingthe residual particulate matter from the filter by removing the adhesivesubstance from the filter together with at least a portion of theresidual particulate matter.